106results about "Generator circuit arrangements control" patented technology

An adaptive, sensorless position sensing apparatus (250) derives rotor position of a synchronous machine (200). The apparatus (250) comprises a first rotor position deriving unit (300) for generating first rotor position values by applying a first sensorless rotor position calculation technique, which emulates a resolver; a second rotor position deriving unit (400) for generating second rotor position values by applying a second sensorless rotor position calculation technique; and a rotor position result output unit (450) for outputting rotor position results over a range of rotor speeds as a function of the first rotor position values, the second rotor position values, and rotor speed.

A hydraulic system includes a variable displacement hydraulic pump connectable to a power source, a hydraulic motor, a fluid circuit, a pump displacement control, and a controller. The pump has an inlet for receiving fluid, an outlet for discharging pressurized fluid, and a pump displacement input. The motor has an inlet for receiving pressurized fluid and an outlet for discharging spent fluid. The fluid circuit includes a supply conduit for conducting fluid discharged by the pump to the motor and a return conduit for returning fluid discharged by the motor to the pump. The pump displacement control cooperates with the pump displacement input to vary pump displacement. The controller communicates with the pump displacement control to control the pump output such that the motor is driven at a constant speed to thereby drive a generator connected to the motor at a constant speed despite speed fluctuations of the power source.

Hydraulic system for driving an auxiliary power source is provided, which is specifically adapted for use with a system for controlling hydraulically driven AC generator. The system includes a hydraulic pump and hydraulic motor that are connected by a fluid circuit. The hydraulic motor drivably connected to an AC generator and is operated in a manner to generate a stable AC power output. The system may include a valve which bypasses fluid around the motor or a variable displacement pump so that the fluid flow rate through the hydraulic motor is controlled in a manner to maintain the desired AC generator output level. Sensors are further provided measuring operating parameters of the system so that the controller can maintain desired operating condition limits

A method of controlling a power converter (258) of a synchronous machine drive system (100) determines position and speed of a rotor (350) of the synchronous machine (300); regulates a current vector relative to a reference frame, having a direct-axis component and a quadrature-axis component, the regulating step selectively causing the current vector to lag a quadrature axis of the machine (300); and outputs a command signal to the power converter (258) as a function of the regulating step. According to one implementation, this process creates higher total torque and maintains supply voltage within a maximum level during a high speed range of the machine.

A method and system for controlling a power converter coupled to a polyphase power line. The method includes measuring at least two motor phase currents, obtaining a floating reference frame for the current Park vector, adjusting the reference frame based on an estimated rotor speed, and controlling the power converter via the floating reference frame to reinitiate power to a motor while a rotor is still moving.

Electronic control for a hydraulic system to drive an auxiliary power source is provided, with an application as a system for controlling the operation of a hydraulically driven AC generator. The system includes a hydraulic pump, a hydraulic motor drivably connected to the generator, and a fluid circuit for circulating fluid from the pump to the motor and back. The feedback circuit contains a feedback conduit to feedback the motor. The system also includes a proportional servo control valve assembly for controlling the fluid conduits and a control circuit for controlling the control valve assembly to thereby control the flow of fluid to the motor. Sensors for measuring the operating parameters of the system and an operator interface module are both able to influence the operation of the system.

A method of protecting a synchronous machine (10) connected to an electricity network (12) against pole-slip comprises the steps of continuously monitoring a power transfer angle (δ) between an electromotive force (EMF) of the machine and a reference voltage V_ref. In the event of a fault (24) on the electricity network which may result in pole-slip of the machine (10), deriving a representation of power transfer (P) relating to the machine against the power transfer angle (δ) utilizing data relating to a value of a current or a voltage measured on a terminal (26) of the machine before the fault has occurred and computed data relating to an expected future value of a current or voltage on the terminal (26), after the fault has occurred. The method then utilizes the representation and a stability criterion to predict whether the machine (10) may become unstable and if instability is predicted, causes the machine (10) to be disconnected at 32 or 34 from the electricity network (12).

A power controller 5 calculates the induced voltage or rotor magnetic flux from the output voltage and the output current of a generator 3, estimates a shaft speed of the generator 3 from the phase of the induced voltage or the phase of the rotor magnetic flux, and calculate the output of a windmill 1 from the estimated value of the shaft speed and the output of the generator 3. As a result, since the output of the windmill 1 can be calculated without requiring a speed sensor for detecting the shaft speed of the generator 3, it is possible to accomplish simplification of circuits, reduction of cost, and high reliability.

The present invention provides a motor rotation angle measurement device and method. The device comprises: a signal conditioning circuit configured to receive three-phase output voltage of a motor and generate first square wave signals, second square wave signals and third square wave signals; and a processor used in one rotation period of the motor and configured to generate one six-multiplying frequency pulse when jumping of any one square wave signal in the first square wave signals, the second square wave signals and the third square wave signals is detected, generate compensation pulse between the current six-multiplying frequency pulse and a next six-multiplying frequency pulse based on the time interval between the current six-multiplying frequency pulse and a previous six-multiplying frequency pulse and a preset compensation subdivision coefficient k, and accumulate the number of the compensation pulse, wherein the number of the compensation pulse is correlated to the rotation angle of the motor. The motor rotation angle measurement device can improve the precision, the reliability and the stability of the rotation angle measurement of the motor and reduce the cost.

An electric machine including: a first part, being a stator or rotor/runner, including a first segment with a first number of mutually spaced poles; a second part, being a rotor/runner or stator, including a second segment with a second number of mutually spaced poles arranged to transduce between electrical and mechanical energy by magnetic interaction with the poles of the first segment, the second segment having substantially the same length as the first segment; and permanent magnets in the poles of the first or second parts, wherein the second number differs from the first number by one to substantially reduce the magnetic interference forces in the direction of motion, wherein gap depths in gaps between the poles of each part are sufficiently deep to substantially attenuate magnetic interactions between a body of each part and the poles of the other part, thereby reducing magnetic interference forces between the first part and the second part, and wherein each part is symmetrical in a direction transverse a direction of motion between the first part and the second part and transverse a depth of the parts for substantially balancing magnetic forces acting perpendicular to the direction of motion.

The invention provides a permanent magnet starter-generator position detection system, and a method. The permanent magnet starter-generator position detection system comprises a current detection circuit, an auxiliary winding, a frequency locking circuit, a phase locking circuit and a control circuit. By adding an auxiliary position sensor and constructing a simulation circuit, the deviation between a phase lock signal of the auxiliary winding and a motor position reference signal under different working modes, rotational speeds and current amplitudes of a starter-generator multiplexed power converter is calibrated. During normal operation, the auxiliary position sensor is removed, and the control circuit compensates the phase locking signal by calibrating the obtained position deviation according to the working mode, the rotational speed and the magnitude of the current of the starter-generator multiplexed power converter, so as to obtain the position information of the permanent magnet starter-generator.

An electrical machine includes a stator having a stator winding and a secondary transformer coil. A rotor is operatively connected to rotate relative to the stator, wherein the rotor includes a plurality of embedded permanent magnets. A primary transformer coil is wound on the rotor and is operatively connected to form a rotating transformer with the secondary transformer coil. An inverter/active rectifier component is operatively connected to the stator winding and the secondary transformer coil to control the stator winding based on a sense in the secondary transformer coil received from the primary transformer coil.

The invention relates to a third-level type motor rotor position estimation method for salient pole characteristic change. Targeted to characteristics of a third-level type motor multi-level combination structure, a new signal transfer and detection channel is established between a main generator and an exciter and is shown as the graph 2; high-frequency signals are injected on the stator side of the main generator through the signal transfer channel, the signals sequentially pass through a main generator air-gap magnetic field, a rotating rectifier and an exciter air-gap magnetic field, then high-frequency response signals are extracted out of an exciter stator winding, and estimation of the position of a motor rotor is achieved. According to the main generator injection-exciter detection signal transfer and detection thought, the characteristic that mutual inductance between the main generator stator winding and the exciter winding changes along with the position of the rotor is fully utilized, and the position of the main generator exciter winding, namely the position of the rotor magnetic pole is estimated. The estimation method does not depend on salient polarity of a motor, and the method is still applicable when the main generator salient polarity changes in the starting process.

In a synchronous machine starting device, an AC voltage detection unit detects AC voltage supplied to an armature of a synchronous machine through an electric power line from a power conversion unit. The AC voltage detection unit has a first output end and a second output end isolated from the electric power line, transforms AC voltage supplied through the electric power line at a first ratio to output the transformed voltage from the first output end, and transforms AC voltage supplied through the electric power line at a second ratio and then limits the transformed voltage to a prescribed positive voltage value or lower and a prescribed negative voltage value or higher for output from the second output end. Then, a detected voltage selection unit selects one of the voltage received from the first output end and the voltage received from the second output end, and outputs the selected one to a rotor position detection unit. The rotor position detection unit detects a rotor position of the synchronous machine based on the voltage received from the detected voltage selection unit. A power conversion control unit controls the power conversion unit based on the detected rotor position.